Changing gearing by sprocket sizes

[Jez]

I think I will try the larger sprocket thing. My chain is still the original, I think at 26K miles, so although it is fine now it will not last forever. I can always go back if I don't like it, right?

Capt says he fitted a 46t rear from an FZS6. Does any one know which model exactly and does it go straight on?

Also what size is the sprocket nut? I probably have a socket but I want to check before hand.